Process and apparatus for winding heavy denier yarn packages



May 29, 1956 R. L. KEEFE, JR 2,747,359

PROCESS AND APPARATUS FOR WINDING HEAVY DENIER YARN PACKAGES Filed Sept.26, 1951 W INVENTOR:

Robert L. l'iiegfegJfl BY Maw A TTORNE Y.

United States Patent PROCESS AND APPARATUS FOR WINDING HEAVY DENIER YARNPACKAGES Robert L. Keefe, J12, Collins l ar-k, Del., assignor to E. I.du Pont de Nemours and Company, Wilmington, Del., a corporation ofDelaware Application September 26, 1951, Serial No. 248,382

4 Claims. (Cl. 5734.5)

This invention relates to a process and apparatus for winding yarnpackages, and relates more particularly to twist winding heavy denieryarn, which is travelling at constant speed from a drawing operation, toproduce yarn packages having a transfer tail and free from anyobjectional non-uniformity of properties.

Drawable yarn, such as nylon, is commonly processed into packages withan apparatus known as a drawtwister, with which the yarn is stretched toa multiple of its original length and wound into a package under tensionwhile simultaneously applying a twist to the yarn. The yarn is suppliedat constant speed by a feed roll to a draw roll, which rotates at ahigher speed to draw the yarn, and then travels directly to a ringtwister which winds the package under tension. The ring twistercustomarily comprises a vertical spindle, the bottom portion of whichrotates in and is supported by a bearing called, a bolster, abelt-driven pulley called a whorl mounted on the spindle above thebolster, an upper portion of the spindle adapted to hold a bobbin orother core for the yarn package, a horizontal ring surrounding thisupper portion of the spindle, a traveler guide slidably supported on thering for guiding the yarn onto the bobbin, and automatic means formoving the ring up and down to build the desired shape of yarn package.Yarn is fed downward to the traveler and thence to the package beingwound at a rate slower than the surface speed of the rotating bobbin,the traveler being forced to rotate and impart twist to the yarn.

In stringing up a ring twister of the kind described, it is commonpractice to take the end of the yarn from the supply package and secureit to the bobbin while holding the spindle at rest with a knee brake,and to thread the yarn through the traveler and the balloon pigtailbefore allowing the spindle to rotate. The next step is to thread theyarn around the various feed and draw rolls which the twister contains.It is, therefore, apparent that the yarn wound onto the bobbin whileperforming the operation of string-up takes the yarn directly from thesupply package without imparting to it any draw except that imparted bythe handling. Consequently, this initially wound yarn in an undrawn orpartially drawn state has widely difierent properties from the uniformlydrawn yarn produced after normal winding conditions are attained. Forexample, this incompletely drawn yarn will dyediffer'ently, have adifferent denier, and have different physical properties from the restof the yarn and, if included in the yarn package, will constitute aserious quality defect in textiles made from the yarn.

It is usual to provide a transfer tail on a yarn package to enable anuninterrupted flow of yarn to be maintained, when a yarn package isdepleted, by tying into a full package on the creel or other multiplepackage holder supporting the yarn package. The transfer tail is woundon the bobbin before winding the main part of the package, this innerend being so disposed as to be positively secured during the winding ofthe yarn package and yet be readily available for tying directly to theouter end of the yarn on another package.

If the transfer tail were initially wound yarn, the package would beobjectionably non-uniform as discussed above. This difficulty can beovercome by collecting the initial yarn on a waste spool during start-upbefore winding the transfer tail, as for example, by depressing thetraveler ring below the normal winding range to the level of the wastespool. However, in the process for handling heavy denier yarns in whichmuch larger packages are normally wound (4 to 10 or 20 pounds ascompared with /2 to 1 pound packages for the fine denier textile yarns),the engineering problems involved in adapting the abovementioned designof tail winder to the heavy denier drawtwister result in a cumbersomeand high-cost device which also entails some safety hazards inoperation.

An object of this invention is to provide a method for winding heavydenier yarn under tension to produce a package having a transfer tailand free from any objectionable non-uniformity of properties. Anotherobject of the invention is to provide a safe, effective and economicalmethod for starting the winding of heavy denier yarn with a ring twisterso as to produce a package which is free from undrawn yarn and has asecure but readily available transfer tail. A further object is toprovide an improved ring twister winding machine for accomplishing theabove objects. Other objects of the invention will become apparent fromthe following description and claims.

The invention will now be described with reference to the preferredembodiment illustrated in the drawings, in which Figure 1 is a frontelevation of essential parts of the improved winding apparatus of thisinvention as it appears when nearly finished winding a yarn package,

Figure 2 is a similar view of the winding apparatus while-starting towind a package,

Figure 3 is a similar view of the winding apparatus while winding thetransfer tail of a package,

Figure 4 is a front elevation, on an enlarged scale, of a string-upguide used when starting up and when winding a transfer tail,

Figure 5 is a cross-section of the outer sleeve of the string-up guide,taken on the line 5-5 of Fig. 4, and

Figure 6 is a top view of the sleeve shown in Fig. 5.

Since the apparatus is an improvement in a winding machine of knownconstruction, only such parts as are necessary to an understanding ofthe invention are shown in Fig. 1. Yarn It) is supplied at constantspeed by suitable means, passes downward through pigtail guide 11,through traveler guide 12, and is wound into yarn package 13 on bobbin14. Traveler 12 is slidably supported on ring 15, which is held by ringholder 16. The ring holder is moved up and down by conventional means tobuild a package of the desired shape. The bobbin is held by a spindle 20which rotates in a spindle bolster 21 supported by machine frame 22. Thespindle is rotated by spindle whorl 23 driven by conventional meansthrough belt 24. A waste spool 25 is provided on the spindle to collectpreliminary windings 26 while stringing up the bobbin on the spindle. Aknee brake 27 is used to stop the spindle when a full bobbin is doffed.The brake presses against the whorl 23 and holds it stationary, the belt24 being arranged so that it will slip over the whorl without grabbingwhen the brake is applied.

A string-up device 39 is used when starting up the winding of a newpackage. This device is shown in greater detail in Figs. 4, 5 and 6. Ayarn guide 31 is mounted on the end of rod 32 which slides inside ofsleeve 33. A bracket 34 is welded to the sleeve and serves to hold theassembly in position on the machine. A slot 35 is machined through theside of the sleeve, and a handle 36 is inserted through the slot andscrewed into the rod 32. This slot extends lengthwise of the sleeve fromnear the bottom of the sleeve to near the top. Midway of the slot is anotch 37 adapted to hold the handle at this intermediate position. Thetop portion of the slot curves 'to one side so that the slot and notchin the sleeve form an f-shaped aperture, or its mirror image, dependingon the direction of rotation of the spindle.

The use of the string-up device is illustrated in Figs. 2 and 3. Instarting up with a new bobbin at a standstill, the yarn is fed downthrough the traveler ring 15, attached to waste spool 25 by winding in aturn or two of the yarn, threaded around yarn guide 31 of the string-updevice so arranged that handle 36 is supported by notch 37 in a positionopposite waste spool 25, thence placed under traveler 12 and throughballoon pigtail 11. The operator then releases the knee brake 27 whichallows the driving belt 24 to rotate the spindle, and yarn is wound onthe waste spool 25. Now with a few quick deft motions, the operatorcompletes the string-up of the position by threading the yarn around thearrangement of feed rolls and draw rolls to permit the production of thedesired drawn yarn. As soon as this string-up is completed and thedesired yarn is being produced, handle 36 of the string-up device isdisengaged from notch 37 and quickly raised to the top extremity of theslot 35, as shown in Fig. 3. This simple motion first guides the yarnaway from the waste spool and onto the bobbin to wind transfer tail 40,and then the curvature of the slot 35 turns the handle to one side anddisengages the yarn from guide 31 when the position shown in Fig. 3 isreached. The traveler 12 then takes over guiding the yarn in theconventional manner with a ring twister winding machine.

The yarn in the resulting transfer tail is identical in every respect tothe yarn wound onto the bobbin in the course of normal operation, exceptthat the yarn in the transfer tail is wound without twist under somewhathigher tension. Since the preferred operation of the drawtwister is at alow level of twist, for example, from up to 1 turn per inch, thedifference in twist in the transfer tail and the normally-wound yarn isimmaterial. Furthermore, when the yarn is unwound from the package, asfor example, in a warping operation, the twist in the transfer tailbecomes nearly identical with that in the rest of the yarn because of abacking up of the twist caused by running over thread guides and becauseof an equalization of twist which occurs in the unsupported yarn lengthbetween two guiding surfaces.

The application of this invention is restricted generally to heavydenier yarn, in that the breaking strength of the yarn must withstandthe tangential force at the waste spool which is imparted by thefrictional drag of the driving belt on the spindle whorl. The wastespool 25 is not a slip spool but is positively driven by the spindlewhich also positively drives the bobbin 14. When winding on the bobbin,the action of the traveler guide in applying twist to the yarn reducesthe effective wind-up speed of the bobbin to a level equal to the rateat which the yarn is fed to it, and the winding machine is designed toprovide a bobbin surface speed which is sufliciently higher than therate of yarn feed to produce the desired amount of twist. The spindle isnormally driven at a high rotational speed, for example, 3000 to 5000 R.P. M. or even higher and, since no twist is applied at the waste spool,because the yarn is fed to it around fixed yarn guide 31, the surfacespeed of the waste spool is considerably higher than the speed at whichthe yarn is delivered to it. Therefore, the yarn must act as a brake onthe whole spindle assembly and cause the driving belt to slip on thespindle whorl to compensate for this difference in speed.

Consequently, it is seen that this invention is limited to the handlingof those yarns whose breaking strength exceeds the frictional drag ofthe driving belt on the spindle whorl. 7

It will be seen from the foregoing description that this invention,although described in connection with the ring twister, would be equallyapplicable to a cap twister or other similar device, whether winding aspool-type package, a single taper package, a double taper package orany permutations thereof. This invention has particular utility incombination with the drawing of fibers which stretch irreversibly, as itprovides for eliminating incompletely drawn yarn from the package andwinds a transfer tail which has the same state of draw, denier and othercharacteristics as the rest of the yarn in the finished package. In thisrespect, it should be noted that the tangential force on the yarn at thewaste spool should be less than the drawing force exerted on the yarn inthe stretching operation. Otherwise, additional drawing might beproduced at the transfer tail string-up guide. The invention is alsouseful for winding strong yarns which are not drawable, although in thisinstance satisfactory results can be obtained with devices of the priorart for winding packages with transfer tails.

This invention is also valuable for repairing yarn breaks occurringduring the winding of a package. When drawing and/or twisting yarn onwinding machines equipped with individual spindle control, it isimpractical to tie the new end to the broken end, since the new end fora distance of several yards is different from the rest of the yarn ineither the state of draw, or the twist, or both, as the case may be.Packages of yarn containing such irregularities would cause mucheconomic loss in the trade where, if such yarn irregularity occurred inthe warp of a fabric for example, it would render the finished fabricvalueless for the entire length of the irregularity. Hence, it has beenthe practice to unwind the partial package, along with the others, andrewinding a new package, which of course, involves stripping out thedefective yarn at the ends of these packages before tying the endstogether to make a continuous length of yarn. However, this is a costlymethod and it is frequently more economical to discard the partialpackages. By an adaptation of the current invention, a new method hasbeen worked out which prevents this economic loss.

With the aid of the removable yarn support described in U. S. Patent No.2,585,584 issued February 12, 1952, to Frank S. Pollock, Jr., andassigned to the assignee of the present application, the invention ofthe current application provides a practical means for repairing yarnbreaks without having to rewind the partially finished packages andlikewise provides a means for positively eliminating the off-standardyarn lengths which normally occur when starting up a spindle on adrawing or twisting machine. When a break occurs, the broken end of theincomplete package is threaded through the removable yarn support (athin sleeve of paper, plastic, metal or other suitable material) andheld taut while the removable yarn support is slipped onto the base ofthe bobbin and over the first transfer tail. The broken end is thuscaught under the thin sleeve and is held firmly in place until wanted.Winding of the package is resumed as if starting up a new package with atransfer tail. That is, the yarn is first wound to a waste take-up spoolat the base of the spindle to receive the first yarn prior to operatingthe individual device for winding the transfer tail.

If no more breaks are obtained, the winding of the package is continueduntil one of normal size is obtained. This package is then doifed andthe removable yarn support is removed from the base of the bobbin tofree the last wound transfer tail (yet leave the first wound transfertail in place), and to permit the loose end thus obtained and the brokenend of the first portion of package to be tied together close to thepackage. After trimming the loose ends of the knot, the resultingpackage does not differ in appearance from a package of unbroken yarnexcept for the presence of this knot and may be used equally well formany purposes.

Of course, if more than one break occurs during the winding of thepackage, the operation simply involves the dofiing of the package ateach break, the tying of the knot to connect the first two portions ofthis partial package, followed by a duplication of the proceduredescribed above for winding another transfer tail on the removable yarnsupport and winding the yarn to the package until another break occursor until the package is of the size desired.

It should be further understood that the removable yarn support,described above, is not essential to the process of winding continuouslength yarn when a break occurs in the winding operation. When theremovable yarn support is not used, it is necessary merely to Wind asomewhat larger first transfer tail, which has its first portionpartially overwound by the subsequent portion to give a firmly anchoredtail. At a yarn break, when it is necessary to wind an additionaltransfer tail, this tail is limited in length so that no portion isoverwound by a subsequent portion. The result is a tail which fallsfreely from the bobbin when the package is lifted to repair the break.The removable yarn support is simply one convenient means for making itpossible to end up with a finished package containing the initialtransfer tail.

As many difierent embodiments of the present invention may be madewithout departing from the spirit and scope thereof, it is to beunderstood that the invention is not limited to the specific embodimentsdisclosed except to the extent defined in the appended claims.

What is claimed is: V I

1. A winding machine for twist-winding yarn packages of heavy denieryarn supplied at constant speed which comprises a rotatable spindlecarrying a whorl, bobbin and a waste spool, said spool being located onthe spindle below and in axial alignment with said bobbin, constantspeed driving means making frictional contact with said whorl andarranged to rotate said spindle at high speed, a traveler guide slidablysupported on a ring surrounding said spindle for guiding yarn onto saidbobbin when winding a package, a stationary guide supported in positionto guide yarn onto said waste spool while stringing up the yarnpreparatory to winding onto said bobbin, means for moving saidstationary guide to a position opposite said bobbin for winding atransfer tail, and means for releasing the yarn from said stationaryguide after the transfer tail has been wound.

2. In a ring-twister winding machine for twist-winding yarn packages ona rotating bobbin carried by a rotating spindle the improvements whichcomprise a waste spool on the spindle below and in axial alignment withthe bobbin and arranged to be rotated with the bobbin, a yarn guidesupported in position to guide yarn onto said spool 6. while stringingup the yarn preparatory to winding onto said bobbin, manually operatedmeans for moving said guide to a position opposite said bobbin forwinding a transfer tail, and means for automatically releasing the yarnfrom said guide as soon as the transfer tail has been wound.

3. In a ring-twister winding machine for twist-winding yarn packages ona rotating bobbin carried by a rotating spindle, the improvements whichcomprise a waste spool mounted on the spindle below and in axialalignment with the bobbin so as to rotate with the bobbin, a fixedsleeve mounted in axial parallelism with the bobbin below the wastespool, a rod slidably supported in the sleeve, a yarn guide hooksupported by said rod in position to guide yarn onto the waste spoolwith the rod in a lower position and to guide yarn onto the bobbin withthe rod in an upper position within the sleeve, a handle attached tosaid rod and projecting through a slot cut through the wall of thesleeve for moving the rod up and down, and said slot having a portioncurved to turn the handle to one side as said hook reaches a positionopposite said bobbin, said curved portion being arranged to cause thehook to turn sufiiciently to release the yarn.

4. In a process for twist-winding yarn packages with heavy denier yarnfed at constant speed on a twister comprising a waste spool and bobbinmounted for positive driving by a spindle, the improvement for winding ayarn package having a transfer tail and free from objectionalnon-uniformity of yarn properties which comprises rotating said spindlewith a frictional driving force which provides a uniform free-runningspeed, feeding heavy denier yarn from a fixed position beyond the end ofsaid bobbin at a constant speed which is less than the freerunningsurface speed of the bobbin, guiding the yarn onto said waste spool froma fixed position to wind the yarn under tension without twisting it,said frictional driving force being such as to place the yarn under ahigher tension than the subsequent twist-winding tension, guiding thetensioned yarn from the waste spool to an end portion of the bobbin towind a transfer tail, and then immediately twist-winding a package undertension on the bobbin adjacent to the transfer tail by guiding the yarnback and forth along the bobbin while revolving the yarn around thebobbin to apply a twist to the yarn.

References Cited in the file of this patent UNITED STATES PATENTS

1. A WINDING MACHINE FOR TWIST-WINDING YARN PACKAGES OF HEAVY DENIER YARN SUPPLIED AT CONSTANT SPEED WHICH COMPRISES A ROTATABLE SPINDLE CARRYING A WHORL, BOBBIN AND A WASTE SPOOL, SAID SPOOL BEING LOCATED ON THE SPINDLE BELOW AND AXIAL ALIGNMENT WITH SAID BOBBIN, CONSTANT SPEED DRIVING MEANS MAKING FRICTIONAL CONTACT WITH SAID WHORL AND ARRANGED TO ROTATE SAID SPINDLE AT HIGH SPEED A TRAVELER GUIDE SLIDABLY SUPPORTED ON A RING SURROUNDING SAID SPINDLE FOR GUIDING YARN ONTO SAID BOBBIN, MEANS ING A PACKAGE, A STATIONARY GUIDE SUPPORTED IN POSITION TO GUIDE YARN ONTO SAID WASTE SPOOL WHILE STRINGING UP THE YARN PREPARATORY TO WINDING ONTO SAID BOBBIN, MEANS FOR MOVING SAID STATIONARY GUIDE TO A POSITION OPPOSITE SAID BOBBIN FOR WINDING A TRANSFER TAIL, AND MEANS FOR RELEASING THE YARN FROM SAID STATIONARY GUIDE AFTER THE TRANSFER TAIL HAS BEEN WOUND. 